1. Field of the Invention
This invention relates the reagent, medium, and method for detection of Alicyclobacilus acidoterrestris. 
2. Description of the Related Art
A wide range of Alicyclobacilus bacteria such as Alicyclobacilus acidocaldarius (hereinafter “acidocaldarius”) and Alicyclobacilus acidoterrestris (hereinafter “acidoterrestris”) exist in soil. Alicyclobacilus bacteria are gram-positive bacillus that form thermophil and acidophil spore, and not killed by usual Pasteur sterilization. Among Alicyclobacilus bacteria, acidoterrestris generate components emitting a foul odor; therefore, it is important to detect the bacteria contamination because it becomes to be a cause of putrefaction.
So far, there is a test method to detect the contamination of acidoterrestris, by which growth of the colony is compared by observing with naked eyes after cultivation for 14-24 hours simultaneously at 2 temperatures of 40-50° C. and 60-70° C. (refer to Japanese Patent Laid-Open No. 2004-41104).
However, because range of temperature at which acidoterrestris can grow is from around 25° C. to 50° C. and that at which acidocaldarius can grow is from 40° C. to 65° C., the above test has had a problem that it is difficult to distinguish the grown colonies between those of acidocaldarius and those of acidoterrestris. 
Therefore, acidoterrestris has been selectively detected by setting the temperature of the culture at around 30° C. so that the growth of acidocaldarius can be inhibited.
However, in the previous test method there has been still another problem that it takes more than 48 hours to detect acidoterrestris because the growth of acidoterrestris is delayed at the temperature around 30° C. although the optimum temperature for the growth of acidoterrestris is around 45° C. Besides, the colonies of grown acidoterrestris on the medium are white and it is another problem that it is difficult to observe the colonies on the semi-transparent medium.
The present invention has focused on such problems and aims to detect acidoterrestris rapidly and to supply the reagent, medium and method for easy detection of Alicyclobacilus acidoterrestris distinguishably from acidocaldarius. 